This implements the principle of "least surprise", in that users won't
normally expect to start overwriting an existing file on these devices.
Real hardware didn't behave that way. A new (empty) file can always
be created with the -N switch on the ATTACH.
- Make all PDP11, VAX RP and RQ devices autosizing behave similarly
- Generalize the attach help to be specific to the device/system being
attached
- Remove the sim_disk_pdp10_* calls which weren't correct or needed
since sim_disk_attach_ex provides sector size which is used correctly
Although these devices interpret a -A switch at attach time, they are not
sequential output devices and thus don't have an ambiguous interpretation
of the switch.
Incorrectly mentioned in #821
The -A attach time switch implicitly means to open files in append
mode.
Some devices used -A to indicate ASCII data or AUTOSIZE of disk or
fixed size tapes - DECtape. These devices are either read only devices
(Paper tape readers or card readers), so explicit forcing of the attach
to be -R avoids unexpected positioning errors. The random access
Disk and fixed sized tapes buffer the container contents in memory
so append mode isn't relevant, but care must be taken to assure that
the buffer reading starts at the beginning of the file without regard
to the explicit open mode.
As reported in #821
Array REGister definitions have been made consistent by passing the
name of the array object. This allows proper sizing assessment
to occur in the register validation logic.
Some previously described array REGister initializers were not really
arrays. Some were structures and others were merely pointers to
someplace in memory that it was desirable to view as a scalar array.
Structures or other blob data should now use SAVEDATA. Virtual
arrays intended to be interpret some part of memory as scalar data
now use VBRDATA initializers.
Array REGister definitions have been made consistent by passing the
address of the whole array object. This allows proper sizing assessment
to occur in the register validation logic.
- Extra queue and timer units on RQB, RQC, and RQD are now properly
initialized.
- PDP11 unit numbers are numbered:
device RQ 0-3
device RQB 4-7
device RQC 8-11
device RQD 12-15
